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secondary 4 | Chemistry
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Why is the answer C?
Date Posted: 3 years ago
Views: 465
2 and 3 are correct because they involve the reaction of an ammonium salt and a base/alkali
Ammonium salt + metallic base/alkali → metallic salt + ammonia + water
For 2,
2 NH4Cl (aq) + Ca(OH)2 (aq) → CaCl2 (aq) + NH3 (g) + H2O (l)
For 3,
(NH4)2SO4 (s) + 2KOH (s) → K2SO4 (s) + 2NH3 (g) + 2H2O (g)
(The heating should be strong enough to cause the water to boil/evaporate)
1 is basically the nitrate test.
3 NaNO3 (aq) + 8 Al (s) + 5 NaOH [(aq) or (s) since state is not given] + 18 H2O (l, comes from the aqueous solution)→8 Na[Al(OH)4] (aq) + 3 NH3 (g)
For 4, nothing much happens.
In NH4Cl (aq) and HCl (aq) , you basically have a mix of NH4+ ions , H+ ions and Cl- ions dissolved in water.
There is no displacement or any reaction.
Ammonium salt + metallic base/alkali → metallic salt + ammonia + water
For 2,
2 NH4Cl (aq) + Ca(OH)2 (aq) → CaCl2 (aq) + NH3 (g) + H2O (l)
For 3,
(NH4)2SO4 (s) + 2KOH (s) → K2SO4 (s) + 2NH3 (g) + 2H2O (g)
(The heating should be strong enough to cause the water to boil/evaporate)
1 is basically the nitrate test.
3 NaNO3 (aq) + 8 Al (s) + 5 NaOH [(aq) or (s) since state is not given] + 18 H2O (l, comes from the aqueous solution)→8 Na[Al(OH)4] (aq) + 3 NH3 (g)
For 4, nothing much happens.
In NH4Cl (aq) and HCl (aq) , you basically have a mix of NH4+ ions , H+ ions and Cl- ions dissolved in water.
There is no displacement or any reaction.
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